Hi K.,
The Next Step formula has more iron in it than regular formula. Too much iron will definately constipate! Also, try giving your daughter things such as whole wheat crackers, whole wheat bagels or bread. Also, green veggies such as green beans and peas have lots of fiber. Also, you can use a little more water in the formula than the can says too. Not much, just 1/4 to 1/2 ounce more water to each scoop than you usually do. The extra water will help to drown the opponent (the constipation)!
With the getting up at night, I dunno. My son is also 9 months old and has never slept through the night. He is always up at that time for a bottle. He is on a combo of pumped breast milk and formula.
The only thing I can think of is that the formula or new foods is giving her gas or a tummy ache. When babies have a tummy ache, they often want something to eat to soothe them. Getting a full tummy lessens the ache.